Ulster players Paddy Jackson and Stuart Olding had denied raping the same woman at Jackson’s home in 2016 and both were unanimously cleared of all charges after a nine-week trial earlier this year.

Jackson and Olding have both been sacked from the club.

After the trial ended on 28 March, Ulster Rugby sent an email to journalists ahead of its press event on 2 April which said “only rugby matters will be discussed”, according to the Belfast Telegraph.

It added: “No comments will be made in relation to the trial or subsequent review.”

Some reporters subsequently asked questions which were deemed unacceptable, leading the club to restrict access to sports journalists only.

It said in a statement that “the conduct of news journalists at a recent press conference negatively impacted our ability to deliver a meaningful event that focused on rugby”.

News reporters are protesting the ban and rugby correspondents have denied the club’s claim that the decision was taken after “consultation with regular press conference attendees”, saying they would not agree to any measures which would prevent their fellow journalists attending.

The open letter, published on Thursday, protested the decision of Ulster Rugby to bar news reporters from pre-match news conferences.

It said: “This attempt to stifle media coverage of the context and consequences of the recent trial is an unjustifiable interference with the freedom of the press, and with the rights of everyone to freedom of information and expression.

“The sports journalists among our membership fully understand the wider public interest in this matter.

“We reject and condemn the attempt by Ulster Rugby to divide us by restricting access to rugby correspondents, while denying other bona fide journalists the right to ask questions and inform their readerships and audiences.

“A free and open media is the cornerstone of democracy in which openness and transparency of information is crucial.”

An Ulster Rugby spokesperson said the club would respond directly to the NUJ.

One of the signatories, Q-Radio news editor David Hunter, added on Twitter: “As a season ticket holder it pained me to have to sign this letter. Ulster Rugby need to engage with fans and media on current issues. When tough questions [have been] asked, they deserve answers.”

On Friday, NUJ assistant general secretary and Irish secretary Seamus Dooley said he hoped Ulster Rugby would agree to meet local union reps and agree to lift the “silly ban” on news reporters.

Earlier last week, Dooley said in a statement: “The NUJ is deeply concerned at the actions of Ulster Rugby. We recognise that there are times when media briefings are of greater interest to sports reporters.

“It would be possible to give priority to sports journalists while facilitating requests from media organisations to accredit news reporters.

“Last week’s statement on the departure of two players was both a news and sports story yet only selected sports journalists were allowed to attend the event.

“This is an unacceptable attempt to control media coverage and seems to me, as Irish secretary of the NUJ, to reflect a wider failure to understand the level of public interest in the story.

“No sporting organisation has a right to shape the news or to seek to divide journalists. Sports journalists fully understand why this issue is not just a sports story.”